CN107925967B - Method and apparatus for power control in D2D/WAN coexistence network - Google Patents

Abstract

Methods, apparatuses, and computer program products for wireless communication are provided. The apparatus may include a memory and at least one processor coupled to the memory configured to determine a transmission condition associated with communication over a wireless channel. The processor may be configured to select a set of open-loop power control parameters of the at least two sets of open-loop power control parameters based on the transmission condition. The processor may be configured to transmit over the wireless channel at a power based on the selected set of open-loop power control parameters. The apparatus may be a wireless device, such as a User Equipment (UE). The open loop power control parameter may be received from a base station, such as a node B or an evolved node B (eNB).

Description

Method and apparatus for power control in D2D/WAN coexistence network

Cross Reference to Related Applications

The present application claims the benefit of U.S. patent application No.14/842,194 entitled "METHOD AND APPARATUS FOR POWER CONTROL IN D2D/WAN COEXISTENCE network" filed on 9/1/2015, which is expressly incorporated herein by reference IN its entirety.

FIELD

The present disclosure relates generally to communication systems, and more particularly to power control mechanisms for coexistence in device-to-device networks and wireless wide area networks.

Background

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasting. Typical wireless communication systems may employ multiple-access techniques capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access techniques include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

These multiple access techniques have been adopted in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate on a city, country, region, and even global level. An example telecommunication standard is Long Term Evolution (LTE). LTE is an enhanced set of Universal Mobile Telecommunications System (UMTS) mobile standards promulgated by the third generation partnership project (3 GPP). LTE is designed to better support mobile broadband internet access by improving spectral efficiency, reducing costs, improving services, utilizing new spectrum, and better integrating with other open standards that use OFDMA on the Downlink (DL), SC-FDMA on the Uplink (UL), and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to grow, there is a need for further improvements in LTE technology. Preferably, these improvements should be applicable to other multiple access techniques and telecommunications standards employing these techniques.

SUMMARY

In an aspect of the disclosure, methods, computer-readable media, and apparatuses are provided. The apparatus may include a memory and at least one processor coupled to the memory configured to determine a transmission condition associated with communication over a wireless channel. The processor may be configured to select a set of open-loop power control parameters of the at least two sets of open-loop power control parameters based on transmission conditions. The processor may be configured to transmit over a wireless channel at a power based on the selected set of open-loop power control parameters. The apparatus may be a mobile station, such as a User Equipment (UE). The open loop power control parameter may be received from a base station, such as a node B or an evolved node B (eNB).

The method may include the operations of: the method includes determining a transmission condition associated with communication over a wireless channel, selecting a set of open-loop power control parameters of at least two sets of open-loop power control parameters based on the transmission condition, and transmitting over the wireless channel at a power based on the selected set of open-loop power control parameters.

A computer-readable medium may store computer executable code for wireless communications, comprising: the apparatus generally includes means for determining a transmission condition associated with communication over a wireless channel, means for selecting a set of open-loop power control parameters of at least two sets of open-loop power control parameters based on the transmission condition, and means for transmitting over the wireless channel at a power based on the selected set of open-loop power control parameters. Other aspects may be described herein.

Brief Description of Drawings

Fig. 1 is a diagram illustrating an example of a network architecture. Fig. 2 is a diagram illustrating an example of an access network.

Fig. 3 is a diagram illustrating an example of a DL frame structure in LTE.

Fig. 4 is a diagram illustrating an example of a UL frame structure in LTE.

Fig. 5 is a diagram illustrating an example of a radio protocol architecture for the user plane and the control plane.

Fig. 6 is a diagram illustrating an example of an evolved node B and user equipment in an access network.

Fig. 7 is a diagram of a device-to-device communication system.

Fig. 8 is a diagram illustrating a conceptual flow of a device-to-device communication system coexisting with a wireless wide area network communication system and an operation for power control in the coexisting network.

Fig. 9 is a flow diagram illustrating a method for power control in a device-to-device and/or wireless wide area network.

Fig. 10 is a conceptual data flow diagram illustrating the data flow between different modules/means/components in an exemplary apparatus.

Fig. 11 is a diagram illustrating an example of a hardware implementation of an apparatus employing a processing system.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details to provide a thorough understanding of the various concepts. It will be apparent, however, to one skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Several aspects of a telecommunications system will now be presented with reference to various apparatus and methods. These apparatus and methods are described in the following detailed description and are illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

By way of example, an element, or any portion of an element, or any combination of elements may be implemented with a "processing system" that includes one or more processors. Examples of such processors include: microprocessors, microcontrollers, Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs), Programmable Logic Devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionalities described throughout this disclosure. One or more processors in the processing system may execute software. Software should be construed broadly to mean instructions, instruction sets, code segments, program code, programs, subprograms, software modules, applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to in software, firmware, middleware, microcode, hardware description language, or other terminology.

Accordingly, in one or more example aspects, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored or encoded as one or more instructions or code on a computer-readable medium. Computer readable media includes computer storage media. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable ROM (EEPROM), compact disk ROM (CD-ROM) or other optical disk storage, magnetic disk storage or other magnetic storage devices, combinations of the above types of computer-readable media, or any other medium which can be used to store computer-executable code in the form of instructions or data structures and which can be accessed by a computer.

Fig. 1 is a diagram illustrating an LTE network architecture 100. The LTE network architecture 100 may be referred to as an Evolved Packet System (EPS) 100. The EPS 100 may include one or more User Equipment (UE)102, an evolved UMTS terrestrial radio access network (E-UTRAN)104, an Evolved Packet Core (EPC)110, and operator Internet Protocol (IP) services 122. The EPS may interconnect with other access networks, but for simplicity those entities/interfaces are not shown. As shown, the EPS provides packet switched services, however, as those skilled in the art will readily appreciate, the various concepts presented throughout this disclosure may be extended to networks providing circuit switched services.

The E-UTRAN includes evolved node Bs (eNBs) 106 and other eNBs 108, and may include Multicast Coordination Entities (MCEs) 128. The eNB 106 provides user plane and control plane protocol terminations towards the UE 102. The eNB 106 may connect to other enbs 108 via a backhaul (e.g., an X2 interface). The MCE 128 allocates time/frequency radio resources for an evolved Multimedia Broadcast Multicast Service (MBMS) (eMBMS) and determines a radio configuration (e.g., a Modulation and Coding Scheme (MCS)) for the eMBMS. The MCE 128 may be a separate entity or part of the eNB 106. The eNB 106 may also be referred to as a base station, a node B, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a Basic Service Set (BSS), an Extended Service Set (ESS), or some other suitable terminology. eNB 106 provides an access point for UE 102 to EPC 110. Examples of UEs 102 include cellular phones, smart phones, Session Initiation Protocol (SIP) phones, laptops, Personal Digital Assistants (PDAs), satellite radios, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablets, or any other similar functioning devices. UE 102 may also be referred to by those skilled in the art as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology.

eNB 106 is connected to EPC 110. EPC 110 may include Mobility Management Entity (MME)112, Home Subscriber Server (HSS)120, other MMEs 114, serving gateway 116, Multimedia Broadcast Multicast Service (MBMS) gateway 124, broadcast multicast service center (BM-SC)126, and Packet Data Network (PDN) gateway 118. MME 112 is a control node that handles signaling between UE 102 and EPC 110. Generally, the MME 112 provides bearer and connection management. All user IP packets are passed through the serving gateway 116, which serving gateway 116 is itself connected to the PDN gateway 118. The PDN gateway 118 provides UE IP address allocation as well as other functions. The PDN gateway 118 and BM-SC 126 are connected to the IP service 122. The IP services 122 may include the internet, intranets, IP Multimedia Subsystem (IMS), PS streaming services (PSs), and/or other IP services. BM-SC 126 may provide functionality for MBMS user service provisioning and delivery. BM-SC 126 may serve as an entry point for content provider MBMS transmissions, may be used to authorize and initiate MBMS bearer services within a Public Land Mobile Network (PLMN), and may be used to schedule and deliver MBMS transmissions. The MBMS gateway 124 may be used to distribute MBMS traffic to enbs (e.g., 106, 108) belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS-related charging information.

Fig. 2 is a diagram illustrating an example of an access network 200 in an LTE network architecture. In this example, the access network 200 is divided into a number of cells 202. One or more lower power class enbs 208 may have a cell area 210 that overlaps with one or more cells 202. The lower power class eNB208 may be a femtocell (e.g., a home eNB (henb)), picocell, microcell, or Remote Radio Head (RRH). Macro enbs 204 are each assigned to a respective cell 202 and are configured to provide an access point to EPC 110 for all UEs 206 in cell 202. In this example of the access network 200, there is no centralized controller, but a centralized controller may be used in alternative configurations. The eNB204 is responsible for all radio related functions including radio bearer control, admission control, mobility control, scheduling, security, and connectivity to the serving gateway 116. An eNB may support one or more (e.g., three) cells (also referred to as sectors). The term "cell" may refer to the smallest coverage area of an eNB and/or an eNB subsystem serving a particular coverage area. Further, the terms "eNB," "base station," and "cell" may be used interchangeably herein.

The modulation and multiple access schemes employed by the access network 200 may vary depending on the particular telecommunications standard being deployed. In LTE applications, OFDM is used on the DL and SC-FDMA is used on the UL to support both Frequency Division Duplex (FDD) and Time Division Duplex (TDD). As those skilled in the art will readily appreciate from the detailed description that follows, the various concepts presented herein are well suited for LTE applications. However, these concepts can be readily extended to other telecommunications standards employing other modulation and multiple access techniques. By way of example, these concepts may be extended to evolution data optimized (EV-DO) or Ultra Mobile Broadband (UMB). EV-DO and UMB are air interface standards promulgated by the third generation partnership project 2(3GPP2) as part of the CDMA2000 family of standards and employ CDMA to provide broadband internet access to mobile stations. These concepts may also be extended to Universal Terrestrial Radio Access (UTRA) employing wideband CDMA (W-CDMA) and other CDMA variants, such as TD-SCDMA; global system for mobile communications (GSM) using TDMA; and evolved UTRA (E-UTRA), IEEE802.11 (Wi-Fi), IEEE 802.16(WiMAX), IEEE 802.20, and Flash-OFDM using OFDMA. UTRA, E-UTRA, UMTS, LTE and GSM are described in literature from the 3GPP organization. CDMA2000 and UMB are described in literature from the 3GPP2 organization. The actual wireless communication standard and multiple access technique employed will depend on the particular application and the overall design constraints imposed on the system.

The eNB204 may have multiple antennas supporting MIMO technology. The use of MIMO technology enables eNB204 to utilize the spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing may be used to transmit different data streams simultaneously on the same frequency. These data streams may be transmitted to a single UE 206 to increase the data rate or to multiple UEs 206 to increase the overall system capacity. This is achieved by spatially precoding each data stream (i.e., applying a scaling of amplitude and phase) and then transmitting each spatially precoded stream over the DL through multiple transmit antennas. The spatially precoded data streams arrive at the UE(s) 206 with different spatial signatures that enable each UE 206 to recover one or more data streams intended for that UE 206. On the UL, each UE 206 transmits a spatially precoded data stream, which enables the eNB204 to identify the source of each spatially precoded data stream.

Spatial multiplexing is typically used when channel conditions are good. Beamforming may be used to concentrate the transmit energy in one or more directions when channel conditions are less favorable. This may be achieved by spatially precoding the data for transmission over multiple antennas. To achieve good coverage at the cell edge, single stream beamforming transmission may be used in conjunction with transmit diversity.

In the following detailed description, various aspects of an access network will be described with reference to a MIMO system supporting OFDM on the DL. OFDM is a spread spectrum technique that modulates data onto a number of subcarriers within an OFDM symbol. These subcarriers are separated by a precise frequency. The separation provides "orthogonality" that enables the receiver to recover the data from the subcarriers. In the time domain, a guard interval (e.g., a cyclic prefix) may be added to each OFDM symbol to combat inter-OFDM symbol interference. The UL may compensate for high peak-to-average power ratio (PAPR) using SC-FDMA in the form of DFT-spread OFDM signals.

Fig. 3 is a diagram 300 illustrating an example of a DL frame structure in LTE. A frame (10ms) may be divided into 10 equally sized subframes. Each subframe may include two consecutive slots. A resource grid may be used to represent 2 slots, where each slot includes a resource block. The resource grid is divided into a plurality of resource elements. In LTE, for a normal cyclic prefix, a resource block contains 12 consecutive subcarriers in the frequency domain and 7 consecutive OFDM symbols in the time domain, for a total of 84 resource elements. For an extended cyclic prefix, a resource block contains 12 consecutive subcarriers in the frequency domain and 6 consecutive OFDM symbols in the time domain, for a total of 72 resource elements. Some of the resource elements indicated as R302, 304 include DL reference signals (DL-RS). The DL-RS includes cell-specific RS (crs) (also sometimes referred to as common RS)302 and UE-specific RS (UE-RS) 304. The UE-RS 304 is transmitted on the resource block to which the corresponding Physical DL Shared Channel (PDSCH) is mapped. The number of bits carried by each resource element depends on the modulation scheme. Thus, the more resource blocks a UE receives and the higher the modulation scheme, the higher the data rate for the UE.

Fig. 4 is a diagram 400 illustrating an example of a UL frame structure in LTE. The resource blocks available for UL may be divided into a data section and a control section. The control section may be formed at both edges of the system bandwidth and may have a configurable size. Resource blocks in the control section may be assigned to the UE for transmission of control information. The data section may include all resource blocks not included in the control section. The UL frame structure results in the data section including contiguous subcarriers, which may allow a single UE to be assigned all of the contiguous subcarriers in the data section.

The UE may be assigned resource blocks 410a, 410b in the control section for transmitting control information to the eNB. The UE may also be assigned resource blocks 420a, 420b in the data section for transmitting data to the eNB. The UE may transmit control information in a Physical UL Control Channel (PUCCH) on the assigned resource blocks in the control section. The UE may transmit data or both data and control information in a Physical UL Shared Channel (PUSCH) on assigned resource blocks in the data section. The UL transmission may span both slots of the subframe and may hop across frequency.

The set of resource blocks may be used to perform initial system access and achieve UL synchronization in a Physical Random Access Channel (PRACH) 430. The PRACH 430 carries a random sequence and cannot carry any UL data/signaling. Each random access preamble occupies a bandwidth corresponding to 6 consecutive resource blocks. The starting frequency is specified by the network. I.e. the transmission of the random access preamble is restricted to certain time-frequency resources. There is no frequency hopping for PRACH. The PRACH attempt is carried in a single subframe (1ms) or in a sequence of several contiguous subframes, and the UE may make a single PRACH attempt per frame (10 ms).

Fig. 5 is a diagram 500 illustrating an example of a radio protocol architecture for the user and control planes in LTE. The radio protocol architecture for the UE and eNB is shown with three layers: layer 1, layer 2 and layer 3. Layer 1(L1 layer) is the lowest layer and implements various physical layer signal processing functions. The L1 layer will be referred to herein as the physical layer 506. Layer 2(L2 layer) 508 is above the physical layer 506 and is responsible for the link between the UE and the eNB above the physical layer 506.

In the user plane, the L2 layer 508 includes a Medium Access Control (MAC) sublayer 510, a Radio Link Control (RLC) sublayer 512, and a Packet Data Convergence Protocol (PDCP)514 sublayer, which terminate at the eNB on the network side. Although not shown, the UE may have several upper layers above the L2 layer 508, including a network layer (e.g., IP layer) terminating at the PDN gateway 118 on the network side, and an application layer terminating at the other end of the connection (e.g., far end UE, server, etc.).

The PDCP sublayer 514 provides multiplexing between different radio bearers and logical channels. The PDCP sublayer 514 also provides header compression for upper layer data packets to reduce radio transmission overhead, security by ciphering the data packets, and handover support for UEs between enbs. The RLC sublayer 512 provides segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and reordering of data packets to compensate for out-of-order reception due to hybrid automatic repeat request (HARQ). The MAC sublayer 510 provides multiplexing between logical channels and transport channels. The MAC sublayer 510 is also responsible for allocating various radio resources (e.g., resource blocks) in one cell among UEs. The MAC sublayer 510 is also responsible for HARQ operations.

In the control plane, the radio protocol architecture for the UE and eNB is substantially the same for the physical layer 506 and the L2 layer 508, except that there is no header compression function for the control plane. The control plane also includes a Radio Resource Control (RRC) sublayer 516 in layer 3 (layer L3). The RRC sublayer 516 is responsible for obtaining radio resources (e.g., radio bearers) and configuring the lower layers using RRC signaling between the eNB and the UE.

Fig. 6 is a block diagram of an eNB610 in communication with a UE 650 in an access network. In the DL, upper layer packets from the core network are provided to a controller/processor 675. The controller/processor 675 implements the functionality of the L2 layer. In the DL, the controller/processor 675 provides header compression, ciphering, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocation to the UE 650 based on various priority metrics. The controller/processor 675 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the UE 650.

A Transmit (TX) processor 616 performs various signal processing functions for the L1 layer (i.e., the physical layer). These signal processing functions include coding and interleaving to facilitate Forward Error Correction (FEC) at the UE 650, and mapping to signal constellations based on various modulation schemes (e.g., Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols are then split into parallel streams. Each stream is then mapped to OFDM subcarriers, multiplexed with reference signals (e.g., pilots) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time-domain OFDM symbol stream. The OFDM stream is spatially precoded to produce a plurality of spatial streams. The channel estimates from channel estimator 674 may be used to determine coding and modulation schemes and for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE 650. Each spatial stream may then be provided to a different antenna 620 via a separate transmitter 618 TX. Each transmitter 618TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 650, each receiver 654RX receives a signal through its respective antenna 652. Each receiver 654RX recovers information modulated onto an RF carrier and provides the information to a Receive (RX) processor 656. The RX processor 656 performs various signal processing functions at the L1 layer. The RX processor 656 may perform spatial processing on the information to recover any spatial streams destined for the UE 650. If multiple spatial streams are destined for the UE 650, they may be combined into a single OFDM symbol stream by an RX processor 656. The RX processor 656 then transforms the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the eNB 610. These soft decisions may be based on channel estimates computed by a channel estimator 658. These soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the eNB610 on the physical channel. These data and control signals are then provided to the controller/processor 659.

The controller/processor 659 implements the L2 layer. The controller/processor can be associated with a memory 660 that stores program codes and data. The memory 660 may be referred to as a computer-readable medium. In the UL, the controller/processor 659 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the core network. These upper layer packets are then provided to a data sink 662, which data sink 662 represents all protocol layers above the L2 layer. Various control signals may also be provided to the data sink 662 for L3 processing. The controller/processor 659 is also responsible for error detection using an Acknowledgement (ACK) and/or Negative Acknowledgement (NACK) protocol to support HARQ operations.

In the UL, a data source 667 is used to provide upper layer packets to the controller/processor 659. The data source 667 represents all protocol layers above the L2 layer. Similar to the functionality described in connection with the DL transmission by the eNB610, the controller/processor 659 implements the L2 layer for the user and control planes by providing header compression, ciphering, packet segmentation and reordering, and multiplexing between logical and transport channels based on radio resource allocations by the eNB 610. The controller/processor 659 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the eNB 610.

Channel estimates, derived by a channel estimator 658 from reference signals or feedback transmitted by the eNB610, may be used by the TX processor 668 to select appropriate coding and modulation schemes, as well as to facilitate spatial processing. The spatial streams generated by the TX processor 668 may be provided to different antennas 652 via separate transmitters 654 TX. Each transmitter 654TX may modulate an RF carrier with a respective spatial stream for transmission.

UL transmissions are processed at the eNB610 in a manner similar to that described in connection with receiver functionality at the UE 650. Each receiver 618RX receives a signal through its respective antenna 620. Each receiver 618RX recovers information modulated onto an RF carrier and provides the information to an RX processor 670. RX processor 670 may implement the L1 layer.

The controller/processor 675 implements the L2 layer. The controller/processor 675 can be associated with a memory 676 that stores program codes and data. The memory 676 may be referred to as a computer-readable medium. In the UL, the controller/processor 675 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the UE 650. Upper layer packets from the controller/processor 675 may be provided to a core network. The controller/processor 675 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

Fig. 7 is a diagram of a device-to-device communication system 700. The device-to-device communication system 700 includes a plurality of wireless devices 704, 706, 708, 710. The device-to-device communication system 700 may overlap with a cellular communication system, such as, for example, a Wireless Wide Area Network (WWAN). Some of the wireless devices 704, 706, 708, 710 may communicate together in a device-to-device communication using the DL/UL WWAN spectrum, some may communicate with the base station 702, and some may do both. For example, as shown in fig. 7, the wireless devices 708, 710 are in device-to-device communication, while the wireless devices 704, 706 are in device-to-device communication. The wireless devices 704, 706 are also communicating with the base station 702.

The exemplary methods and apparatus discussed below are applicable to any of a variety of wireless device-to-device communication systems, such as, for example, wireless device-to-device communication systems based on FlashLinQ, WiMedia, bluetooth, ZigBee, or Wi-Fi based on the IEEE802.11 standard. To simplify the discussion, exemplary methods and apparatus are discussed within the context of LTE. However, one of ordinary skill in the art will appreciate that these exemplary methods and apparatus are more generally applicable to various other wireless device-to-device communication systems.

Fig. 8 is a diagram illustrating a communication system 800 with a device-to-device (D2D) network coexisting with a WWAN. The WWAN network includes, but is not limited to, a base station 802 and a first wireless device 806, which may also be referred to as a mobile station, UE, etc. The base station 802 may provide a cell 804 on which a first wireless device 806 may operate. In doing so, the base station 802 and the wireless device 806 may communicate together using the DL/UL WWAN spectrum. In an aspect, the base station 802 configures resources on which the wireless device 806 will transmit uplink signals 820. For example, the base station 802 may transmit a downlink signal 822 on a resource corresponding to a Physical Downlink Control Channel (PDCCH) to schedule user data to be transmitted by the wireless device 806 in an uplink signal 820 on a resource corresponding to a PUSCH.

The D2D network includes, but is not limited to, a plurality of wireless devices 814, 816, at least one of which may also be referred to as a mobile station, UE, etc. The wireless devices 814, 816 may form at least a portion of a D2D network. The D2D network may overlap with a cellular communication system (such as a WWAN) where the base station 810 provides a cell 812 on which the wireless devices 814, 816 may operate. However, in some aspects, such as where the wireless devices 814, 816 are not operating on a cell (e.g., the wireless devices 814, 816 may be outside of a coverage area), the base station 810 may not be present. The wireless devices 814, 816 may communicate together in D2D communications using the DL/UL WWAN spectrum or another spectrum (e.g., an unlicensed spectrum). In an aspect, the base station 810 configures resources for which the wireless devices 814, 816 are to communicate in the D2D network.

D2D communication between the wireless devices 814, 816 may include a discovery process between the wireless devices 814, 816. For example, advertiser wireless device 814 may broadcast a discovery signal, and upon detecting the discovery signal, monitoring wireless device 816 may transmit a response to advertiser wireless device 814, e.g., to synchronize and/or establish timing information for facilitating D2D communication between advertiser wireless device 814 and monitoring wireless device 816.

For coexistence of a D2D network and a WWAN in the communication system 800, adaptive power control of one or more of the wireless devices 806, 814, 816 may mitigate interference to another of the wireless devices 806, 814, 816 and/or one of the base stations 802, 810. In an example, when D2D transmission occurs between the second wireless device 814 and the third wireless device 816 (e.g., in the neighboring cell 812), inter-cell interference may occur with the first wireless device 806 transmitting an uplink signal 820 to the base station 802. That is, the uplink signal 820 may introduce interference 824 to a D2D signal 826 (e.g., a discovery signal) communicated between the second wireless device 814 and the third wireless device 816. As such, uplink signal 820 may cause interference 824 to wireless device 814. Similarly, D2D signal 826 may introduce interference 828 into the uplink signal 820 between the wireless device 806 and the base station 802. As such, D2D signal 826 may cause interference 828 to base station 802. Similarly, D2D signal 826 may introduce interference 830 into downlink signal 822 between wireless device 806 and base station 802. As such, the D2D signal 826 may cause interference 830 to the first wireless device 806.

In an exemplary aspect, one or more resources configured for the same subframe of D2D signal 826 may overlap with resources configured for uplink signal 820. For example, the uplink signal 820 may be carried on resources corresponding to PUCCH/PUSCH, and at the same time the D2D signal 826 may be carried on resources that overlap with PUCCH/PUSCH in the neighboring cell 804. When the second wireless device 814 approaches the boundary of the first cell 804 where the uplink signal 820 is transmitted, the uplink signal 820 of the first wireless device 806 may introduce interference 824 into a D2D signal 826 communicated between the second wireless device 814 and the third wireless device 816, resulting in a loss of data from the transmitting wireless device (e.g., the third wireless device 816) to the receiving wireless device (e.g., the second wireless device 814). Similarly, when uplink signals 820 communicated between the first wireless device 806 and the base station 802 are transmitted on resources that overlap with resources carrying D2D signals 826, D2D signals 826 communicated between the second wireless device 814 and the third wireless device 816 may introduce interference 828 to the uplink signals 820. Further, D2D signals 826 communicated between the second wireless device 814 and the third wireless device 816 may introduce interference 830 to the downlink signals 822 when the downlink signals 822 communicated between the first wireless device 806 and the base station 802 are transmitted on resources (e.g., Physical Downlink Control Channel (PDCCH) and/or Physical Downlink Shared Channel (PDSCH)) that overlap with resources carrying the D2D signals 826.

To mitigate interference, one or more of the wireless devices 806, 814, 816 may be configured to control the transmission power of the respective transmitted signals 820, 826. Transmission power control may balance the need to transmit energy per bit sufficient to maintain link quality corresponding to a required quality of service (QoS) with minimizing interference to other wireless devices. The approaches to power control of transmissions disclosed herein may mitigate interference occurring in subframe(s) and/or subcarrier(s), and may be applicable to aspects in which communication system 800 is a TDD network or an FDD network.

According to aspects, each of the wireless devices 806, 814, 816 controls its respective transmission power based on a power control algorithm. One of the wireless devices 806, 814, 816 calculates at least one value to control its respective transmission power based on a plurality of parameters associated with a power control algorithm. The power control algorithm may be defined by one or more standards associated with WWAN and/or D2D communication, such as one or more 3GPP technical specifications. The first wireless device 806 may utilize a power control algorithm for WWAN communication and may actually utilize a different power control algorithm depending on the type of communication (e.g., data or control) and/or the type of wireless channel. Similarly, the second wireless device 814 and the third wireless device 816 may utilize power control algorithms for D2D communication, and may utilize different power control algorithms depending on the type of communication (e.g., data or control) and/or the type of wireless channel. It is to be appreciated that the first wireless device 806 may be capable of D2D operations as described herein with respect to the second and third wireless devices 814, 816, and as such, the second wireless device 814 and/or the third wireless device 816 may be capable of WWAN operations as described herein with respect to the first wireless device 806.

When the closed-loop parameters may be associated with a power control scheme employed by at least one of the wireless devices 806, 814, 816, the closed-loop feedback may compensate for a situation in which one of the wireless devices 806, 814, 816 estimates its respective power setting and finds the respective power setting unsatisfactory, and thus the closed-loop parameters are not considered by the power control mechanism of the present disclosure.

In the power control schemes of the present disclosure, at least one of the wireless devices 806, 814, 816 may control the respective transmission power based on a plurality of open loop power control parameters. A first one of the open-loop power control parameters may be a semi-static base power level P₀And a second one of the open loop power control parameters may be a path loss compensation component alpha. According to aspects, the semi-static base power level P₀May be specific to each of the wireless devices 806, 814, 816 or to one of the cells 804, 812 in which the wireless device 806, 814, 816 is located, and the path loss compensation component a may be specific to each of the wireless devices 806, 814, 816. In other aspects, at least one of the wireless devices 806, 814, 816 may be based on different and/or additional devicesThe added open loop power control parameter controls its corresponding transmit power, and thus P₀And alpha will be considered illustrative.

In accordance with an aspect, the set of one or more open loop power control parameters may be signaled to the wireless device 806, 814, 816. For example, the first base station 802 may signal one or more sets of open loop power control parameters to the first wireless device 806 using System Information Blocks (SIBs), RRC signaling, or other dedicated signaling. Similarly, the second base station 810 may signal one or more sets of open loop power control parameters to the second and third wireless devices 814, 816.

In an aspect, at least one of the wireless devices 806, 814, 816 may have two different sets of open-loop power control parameters, e.g., [ P ]₀，α]₀And [ P₀，α]₁. Employing, by at least one of the wireless devices 806, 814, 816, the two sets of open-loop power control parameters [ P ] based on at least one transmission condition associated with transmission by at least one of the wireless devices 806, 814, 816 on a wireless channel₀，α]₀And [ P₀，α]₁. In aspects, one or more sets of open-loop power control parameters may have one or more values in common with each other.

At least one open loop power control parameter set (e.g., [ P ]₀，α]₀) Can be considered as a set of open loop power control parameters for transmission conditions where the interference does not require adaptive power control. The first set of open loop power control parameters (e.g., [ P ]₀，α]₀) May be considered a default open loop power control parameter set. For example, the first wireless device 806 may use this first set of open loop power control parameters when the resources over which the first wireless device 806 will communicate do not overlap with the resources over which the second and third wireless devices 814, 816 will communicate.

According to aspects, in the event that one of the wireless devices 806, 814, 816 detects a transmission condition indicating unlikely and/or insignificant interference, a first set of open-loop power control parameters (e.g., [ P ] s)₀，α]₀) May be employed by at least one of the wireless devices 806, 814, 816. For example, the first wireless device 806 may determine the transmission condition based on an indication that resources allocated for uplink and/or downlink transmissions do not coincide/overlap with resources allocated for D2D communications (such as D2D signals 826). The first wireless device 806 can receive the indication, such as from the base station 802 (which can receive resource and/or subframe allocation information from the neighboring base station 810 over a backhaul and/or X2 interface).

In an aspect, the first wireless device 806 may determine the transmission condition by, for example, detecting interference during unused resources (e.g., open subframes) where the first wireless device 806 is not transmitting and/or receiving. In the event that the first wireless device 806 does not detect interference 830, the first wireless device 806 may perform a selection operation 832 to select a first set of open-loop power control parameters P₀，α]₀(e.g., a default open loop power control parameter set). Accordingly, the first wireless device 806 may use the selected first set of open-loop power control parameters P₀，α]₀To calculate the power of the transmission of uplink signal 820 to base station 802.

In another aspect, the first wireless device 806 may detect the interference 830 and measure the energy (or power) of the interference 830. The first wireless device 806 may compare the measured energy to a threshold and if the measured energy does not meet or exceed the threshold, the first wireless device 806 may perform a selection operation 832 to select a first set of open-loop power control parameters P₀，α]₀(e.g., a default open loop power control parameter set). Accordingly, the first wireless device 806 may use the selected first set of open-loop power control parameters P₀，α]₀To calculate the power of the transmission of uplink signal 820 to base station 802.

However, if the first wireless device 806 determines that the measured energy exceeds the threshold (or that the threshold is met in an alternative configuration), the first wireless device 806 may determine that the transmission conditions require use of a second set of open-loop power control parameters P₀，α]₁For calculating the transmission of uplink signals 820 to base station 802And (4) power. Thus, the first wireless device 806 may perform a selection operation 832 to select a second set of open-loop power control parameters P₀，α]₁. Accordingly, the first wireless device 806 may use the selected second set of open-loop power control parameters P₀，α]₁To calculate the power of the transmission of uplink signal 820 to base station 802.

Similarly, the second wireless device 814 may determine the transmission condition by detecting interference, e.g., during unused resources (e.g., open subframes) where the second wireless device 814 is not transmitting and/or receiving. In the event that the second wireless device 814 does not detect interference 824, the second wireless device 814 may perform selection operation 834 to select a first set of open-loop power control parameters [ P [ ]₀，α]₀(e.g., a default open loop power control parameter set). Accordingly, the second wireless device 814 may use the selected first set of open-loop power control parameters [ P [ ]₀，α]₀To calculate the power of the transmission of D2D signal 826.

In another aspect, the second wireless device 814 may detect the interference 824 and measure the energy (or power) of the interference 824. The second wireless device 814 may compare the measured energy to a threshold and if the measured energy does not meet or exceed the threshold, the second wireless device 814 may perform a selection operation 834 to select a first set of open-loop power control parameters P₀，α]₀(e.g., a default open loop power control parameter set). Accordingly, the second wireless device 814 may use the selected first set of open-loop power control parameters [ P [ ]₀，α]₀To calculate the power of the transmission of D2D signal 826.

However, if the second wireless device 814 determines that the measured energy exceeds the threshold (or, in an alternative configuration, the threshold is met), the second wireless device 814 may determine that the transmission conditions require use of a second set of open-loop power control parameters [ P [ ]₀，α]₁To calculate the power of the transmission of D2D signal 826. Accordingly, the second wireless device 814 may perform a selection operation 834 to select a second set of open-loop power control parameters P₀，α]₁. Accordingly, the second wireless deviceThe device 814 may use the selected second set of open-loop power control parameters P₀，α]₁To calculate the power of the transmission of D2D signal 826.

According to aspects, the third wireless device 816 may select the first set of open-loop power control parameters P in a manner similar to that described for the second wireless device 814₀，α]₀(e.g., a default open loop power control parameter set). For example, the third wireless device 816 may detect a transmission condition based on measuring the energy of the interference 824 and comparing the measured energy to a threshold.

At least one of the wireless devices 806, 814, 816 may have multiple sets of open-loop power control parameters, e.g., [ P ]₀，α]₀、...、[P₀，α]_NWherein N is greater than or equal to 1. Employing, by at least one of the wireless devices 806, 814, 816, each set of open-loop power control parameters [ P ] based on at least one transmission condition associated with transmission by at least one of the wireless devices 806, 814, 816 on a wireless channel₀，α]₀、...、[P₀，α]_N。

For example, the second set of open-loop power control parameters (e.g., [ P ]) may be transmitted by at least one of the wireless devices 806, 814, 816₀，α]₁) For transmission conditions where one of the wireless devices 806, 814, 816 may cause interference to another signal. In an aspect, the second set of open-loop power control parameters may cause one of the wireless devices 806, 814, 816 to reduce the transmission power.

Alternatively or in addition to the second set, one of the wireless devices 806, 814, 816 may also have a third set of open-loop power control parameters (e.g., [ P ])₀，α]₂). The third set of open loop power control parameters may be used by at least one of the wireless devices 806, 814, 816 for transmission conditions in which a receiving side of a signal transmitted by one of the wireless devices 806, 814, 816 (e.g., the base station 802, the second wireless device 814, or the third wireless device 816) may experience interference. For example, the third set of open loop power control parameters may cause the wireless devices 806, 814 to,816 increases the transmission power.

By way of illustration, the first wireless device 806 may determine that the first wireless device 806 may cause interference to D2D communications (e.g., D2D discovery) between the second and third wireless devices 814, 816 based on an indication that resources allocated for uplink transmissions may overlap with resources allocated for D2D communications. The first wireless device 806 can receive the indication, such as from the base station 802 (which can receive resource and/or subframe allocation information from the neighboring base station 810 over a backhaul and/or X2 interface).

In an aspect, the first wireless device 806 may detect for interference, e.g., during unused resources (e.g., open subframes) that the first wireless device 806 is not transmitting and/or receiving. In the event that the first wireless device 806 detects interference 830, the first wireless device 806 may measure the energy of the interference 830 and compare the measured energy to a threshold.

Based on the comparison, the first wireless device 806 may determine a transmission condition in which the first wireless device 806 may cause interference to the D2D signal 826, such as when the third wireless device 816 broadcasts a D2D discovery signal that is detectable by the wireless device 814. For example, when the energy of the interference 830 from the D2D signal 826 meets or exceeds a threshold, the first wireless device 806 may determine that the uplink signal 820 may cause interference 824 to the second wireless device 814 when receiving the D2D signal 826 from the third wireless device 816. In response, the first wireless device 806 may perform a selection operation 832 to select a set of open-loop power control parameters stored therein (e.g., with a default set [ P ]₀，α]₀A second, different set [ P ]₀，α]₁). Accordingly, the first wireless device 806 may calculate a reduced transmission power using the selected set of open-loop power control parameters to mitigate interference 824 to the second wireless device 814 and may transmit the uplink signal 820 with the reduced transmission power.

It should be appreciated that although aspects of the present disclosure describe the interference 828, 830 as originating from the D2D signal 826, similar operations may be performed by the first wireless device 806 when interference is detected from the WWAN signal in the neighboring cell 812. For example, the resources carrying the uplink signal 820 from the first wireless device 806 may overlap with the resources carrying the uplink signal from the second wireless device 814 to the neighboring base station 810 in the neighboring cell 812, and the first wireless device 806 may detect the transmission condition and perform selection operation 832 to mitigate interference from the uplink signal in the neighboring cell 812.

In another illustrative aspect, the second wireless device 814 may determine that the D2D signal 826 may cause interference 830 to the first wireless device 806 and/or may cause interference 828 to the base station 802 based on an indication that resources allocated for D2D communication may overlap with resources allocated for uplink and/or downlink transmissions (such as uplink and/or downlink signals 820,822 in the neighboring cell 804). The second wireless device 814 may receive the indication, such as from the base station 810 (which may receive resource and/or subframe allocation information from the neighboring base station 802 over a backhaul and/or X2 interface).

In an aspect, the second wireless device 814 may detect interference, e.g., during unused resources (e.g., open subframes) that the second wireless device 814 is not transmitting and/or receiving. In the event that the second wireless device 814 detects interference 824, the second wireless device 814 may measure the energy of the interference 824 and compare the measured energy to a threshold.

Based on the comparison of the measured energy to the threshold, the second wireless device 814 may determine a transmission condition in which the D2D signal 826 may interfere with a receiver (such as the first wireless device 806 and/or the base station 802 of the neighboring cell 804). When the measured energy of the interference 824 from the uplink and/or downlink signals 820,822 meets or exceeds a threshold, the second wireless device 814 may determine that the D2D signal 826 may cause interference 830 to the first wireless device 806 when receiving the downlink signal 822 and/or that the D2D signal 826 may cause interference 828 to the base station 802 when receiving the uplink signal 820. In response to the determined transmission condition, the second wireless device 814 may perform a selection operation 834 to select a set of open-loop power control parameters (e.g., different from the default set [ P ]₀，α]₀Second set [ P ] of₀，α]₁). The selected set of open-loop power control parameters may reduce the transmission power of the D2D signal 826 to mitigate interference to the receiver (e.g., the first wireless device 806 and/or the base station 802). Accordingly, the second wireless device 814 may calculate a reduced transmit power using the selected set of open-loop power control parameters and may transmit the D2D signal 826 at the reduced transmit power.

In another illustrative aspect, the third wireless device 816 may determine that a D2D signal 826 (such as a D2D discovery signal) transmitted by the third wireless device 816 may experience interference at the receiving side based on an indication that resources allocated for D2D communication may overlap with resources allocated for uplink and/or downlink transmissions (such as uplink and/or downlink signals 820,822 in the neighboring cell 804). The third wireless device 816 can receive the indication, such as from the base station 810 (which can receive resource and/or subframe allocation information from the neighboring base station 802 over a backhaul and/or X2 interface).

In an aspect, the third wireless device 816 may detect interference, for example, during unused resources (e.g., open subframes) that the third wireless device 816 is not transmitting and/or receiving. In the event that the third wireless device 816 detects interference 824, the third wireless device 816 may measure the energy of the interference 824 and compare the measured energy to a threshold.

Based on the comparison of the measured energy to the threshold, the third wireless device 816 may determine a transmission condition in which the receiving side (e.g., the second wireless device 814) may experience interference when receiving the D2D signal 826. For example, the interference 824 may prevent D2D discovery by the third wireless device 816. In response to the determined transmission condition, the third wireless device 816 may perform a selection operation 836 to select a set of open-loop power control parameters (e.g., different from the default set [ P ]₀，α]₀Second set [ P ] of₀，α]₁). The selected set of open-loop power control parameters may increase the transmission power of the D2D signal 826 to improve reception and/or decoding of the D2D signal 826 by the second wireless device 814 (e.g., while the second wireless device 814 is monitoring D2D)When a signal is found). Accordingly, the third wireless device 816 may calculate an increased transmission power using the selected set of open-loop power control parameters, and may transmit the D2D signal 826 at the increased transmission power.

It should be appreciated that although aspects of the present disclosure describe the interference 824 as originating from uplink and/or downlink signals 820,822 in the WWAN, similar operations may be performed by the second wireless device 814 and/or the third wireless device 816 when interference is detected from a D2D signal, such as a D2D signal in the neighboring cell 804. For example, the resources carrying the D2D signal 826 may overlap with the resources carrying another D2D signal from the first wireless device 806, and the second wireless device 814 may detect the transmission condition and perform the selection operation 834 to mitigate interference from other D2D signals.

According to various aspects, the respective selection operations 832, 834, 836 performed by the respective wireless devices 806, 814, 816 may be a function of the detected interference. As described in this disclosure, at least one of the wireless devices 806, 814, 816 may have multiple sets of open-loop power control parameters. According to an aspect, the respective wireless device 806, 814, 816 may perform a respective selection operation 832, 834, 836 to select a set of open-loop power control parameters corresponding to the measured interference energy. Indeed, at least one of the wireless devices 806, 814, 816 may incrementally adjust the transmission power such that the transmission power is commensurate with the measured interference energy.

In an illustrative aspect, at least one of the wireless devices 806, 814, 816 may have multiple thresholds against which one of the wireless devices 806, 814, 816 may compare the measured interference energy. That is, one of the wireless devices 806, 814, 816 may measure an interference energy that meets or exceeds the first threshold but does not meet or exceed the second threshold. Accordingly, for example, one of the wireless devices 806, 814, 816 may select a set of open-loop power control parameters corresponding to the measured energy such that one of the wireless devices 806, 814, 816 unsatisfactorily increases or decreases the transmission power.

For example, depending on whether the D2D signal 826 is transmitted by the second wireless device 814 or the third wireless device 816 (e.g., the first wireless device 806 may be closer to the second wireless device 814 than the third wireless device 816), the first wireless device 806 may measure different energies of the interference 830. As described above, the first wireless device 806 may measure the energy of the interference 830 and may compare the measured energy to a threshold. Although in further aspects, the first wireless device 806 may compare the measured energy to a plurality of thresholds. In the event that the first wireless device 806 determines that the measured energy meets or exceeds the first threshold but does not meet or exceed the second threshold, the first wireless device 806 may perform a selection operation 832 to select a set of open loop power control parameters corresponding to measured energy that meets or exceeds the first threshold but not the second threshold. Accordingly, the first wireless device 806 can calculate the power of the transmission of the uplink signal 820 to the base station 802 using the selected set of open-loop power control parameters. For example, the first wireless device 806 can select a set of open loop power control parameters that reduce the power used to transmit the uplink signal 820 to mitigate the interference 824, but that do not reduce the transmission power to a level at which the base station 802 cannot receive and decode the uplink signal 820.

In another example, the second wireless device 814 may measure different energies of the interference 824 depending on whether the uplink signal 820 or the downlink signal 822 causes the interference 824 (e.g., the signal from the first wireless device 806 may have a greater energy than the signal from the base station 802, as measured at the second wireless device 814). As described above, the second wireless device 814 may measure the energy of the interference 824 and may compare the measured energy to a threshold. Although in further aspects, the second wireless device 814 may compare the measured energy to a plurality of thresholds. In the event that the second wireless device 814 determines that the measured energy meets or exceeds the first threshold but does not meet or exceed the second threshold, the second wireless device 814 may perform a selection operation 834 to select a set of open-loop power control parameters corresponding to measured energy that meets or exceeds the first threshold but not the second threshold. Accordingly, the second wireless device 814 may calculate the power of the transmission of the D2D signal 826 using the selected set of open-loop power control parameters. For example, the second wireless device 814 may select a set of open-loop power control parameters that increase power for transmission of the D2D signal 826 such that the third wireless device 816 may receive and decode the D2D signal 826, but the selected set of open-loop power control parameters may not increase the transmission power for the D2D signal 826 to a point where the D2D signal 826 would unacceptably interfere with the uplink signal 820 and/or the downlink signal 822.

It should be understood that although aspects of the present disclosure describe two thresholds, at least one of the wireless devices 806, 814, 816 may have any number of thresholds and any number of sets of open-loop power control parameters. For example, at least one of the wireless devices 806, 814, 816 may have a first threshold corresponding to selection of a default set of open-loop power control parameters, a second threshold corresponding to selection of a set of open-loop power control parameters resulting in a smaller increase in transmission power, a third threshold corresponding to selection of a set of open-loop power control parameters resulting in a larger increase in transmission power, a fourth threshold corresponding to selection of a set of open-loop power control parameters resulting in a smaller decrease in transmission power, a fifth threshold corresponding to selection of a set of open-loop power control parameters resulting in a larger decrease in transmission power, and so on.

The present disclosure may reference discrete quantities of open loop power control parameters; however, such quantities will be considered illustrative, and the wireless devices 806, 814, 816 may each have a different number of open loop power control parameters, e.g., a respective one of the wireless devices 806, 814, 816 may have a set of open loop power control parameters for a plurality of channels to be used if adaptive power control is not required for interference, a set of open loop power control parameters for a plurality of channels to be used if adaptive power control is not actually required for interference when the respective one of the wireless devices 806, 814, 816 communicates over the WWAN, a set of open loop power control parameters for a plurality of channels to be used if adaptive power control is not required for interference when the respective one of the wireless devices 806, 814, 816 communicates in D2D, and so on.

In accordance with an aspect, at least one of the wireless devices 806, 814, 816 may have different sets of open-loop power control parameters to employ for resources corresponding to or overlapping different wireless channels. For example, at least one of the wireless devices 806, 814, 816 may have a first set of open loop power control parameters to control the transmission power of signals carried on resources corresponding to or overlapping with PUSCH and a second set of open loop power control parameters to control the transmission power of signals carried on resources corresponding to or overlapping with PUCCH.

In an aspect, the wireless device 806 of the WWAN may select different sets of open loop power control parameters for resources corresponding to or overlapping different wireless channels associated with WWAN communication. For example, where the uplink signal 820 is a control or data signal, the first wireless device 806 may transmit control information on resources corresponding to the PUCCH and/or may transmit data on resources corresponding to the PUSCH, respectively. The first wireless device 806 may have a first set of open loop power control parameters to control the transmission power of signals carried on resources corresponding to the PUCCH and a second set of open loop power control parameters to control the transmission power of signals carried on resources corresponding to the PUSCH.

In another aspect, at least one of the wireless devices 814, 816 of the D2D network may select different sets of open-loop power control parameters for resources corresponding to or overlapping different wireless channels associated with D2D communications. For example, where D2D signal 826 is a control or data signal (e.g., after a D2D discovery procedure), a transmitting device (e.g., the second wireless device 814 or the third wireless device 816) may transmit control information on resources corresponding to a Physical Sidelink Control Channel (PSCCH) and/or may transmit data on resources corresponding to a physical sidelink shared channel (PSCCH), respectively. At least one of the wireless devices 814, 816 of the D2D network may have a first set of open-loop power control parameters to control the transmission power of signals carried on resources corresponding to the PUCCH and a second set of open-loop power control parameters to control the transmission power of signals carried on resources corresponding to the PUSCH.

Fig. 9 is a flow chart illustrating a method for power control in a device-to-device and/or wireless wide area network. Method 900 may be performed by a wireless device, such as one of wireless devices 806, 814, 816 of fig. 8.

Fig. 9 may begin with operation 902 in which a wireless device is to determine transmission conditions associated with communicating over a wireless channel. In an aspect, a wireless device may receive an indication of resources to be used for another communication (e.g., in a neighboring cell). In an additional aspect, the wireless device may detect interference (e.g., on those resources indicated as being used for another communication).

In an aspect, operation 902 may include an aspect of operation 904. In an aspect of operation 904, the wireless device may determine whether a communication of the wireless device is on the same set of resources as another communication. For example, the transmission condition may be associated with D2D communication by another wireless device using the same set of resources as the wireless device. In the context of fig. 8, the first wireless device 806 may receive an indication of resources to be used for D2D signals 826 in the neighboring cell 812.

In another aspect of operation 904, the transmission condition can be associated with an allocation of WWAN resources of a neighboring base station. In the context of fig. 8, one of the wireless devices 814, 816 may receive an indication of resources to be used for uplink signals 820 and/or downlink signals 822 in the neighboring cell 804.

An aspect of operation 902 may include operation 906. In an aspect of operation 906, the wireless device may determine whether it is causing interference to another wireless device (or determine that a signal transmitted by the wireless device is interfered by another wireless device). In an aspect of operation 906, the first wireless device 806 of fig. 8 may detect interference 830 from the D2D signal 826. For example, the first wireless device 806 may detect interference during open resources during which the wireless device 806 is not transmitting or receiving. The first wireless device 806 can compare the energy (or power) of the detected interference to a threshold to determine a transmission condition.

In another aspect of operation 906, one of the wireless devices 814, 816 may detect interference 824 from uplink signals 820 and/or downlink signals 822. For example, one of the wireless devices 814, 816 may measure the energy (or power) of interference during open resources during which one of the wireless devices 814, 816 is not transmitting or receiving. One of the wireless devices 814, 816 may compare the energy (or power) of the measured interference to a threshold to determine a transmission condition.

Proceeding to operation 908, the wireless device may determine whether the transmission conditions indicate that resources to be used by the wireless device for communication may interfere with another communication. In an aspect, a wireless device may determine, based on an indication of resources to be used for another communication, that a transmission condition indicates that resources to be used for communication by the wireless device would interfere with the other communication. The wireless device may determine that the communication of the wireless device may interfere with the other communication if the resources allocated for communication by the wireless device are also indicated as being allocated for the other communication.

In the context of fig. 8, the first wireless device 806 may receive an indication that D2D communication is to occur in the neighboring cell 812, e.g., on the same resources as the first wireless device 806 will use for the uplink signal 820. In a further aspect, the first wireless device 806 may determine whether the measured interference meets or exceeds a threshold amount, indicating whether the uplink signal 820 may introduce interference 824 to the D2D signal 826. If the measured interference meets or exceeds the threshold, the first wireless device 806 may determine that the uplink signal 820 may introduce interference 824 to the D2D signal 826. Otherwise, the first wireless device 806 may determine that the uplink signal 820 is unlikely to introduce interference 824 to the D2D signal 826.

Alternatively, the second or third wireless device 814, 816 may receive an indication that the D2D communication is to occur in the neighboring cell 804, e.g., on the same resources as the second and third wireless device 814, 816 are to be used for D2D signals 826. In an aspect, the second or third wireless device 814, 816 may determine whether the measured interference meets or exceeds a threshold amount, which indicates whether D2D signal 826 may introduce interference 830 to uplink signal 820 and/or downlink signal 822 and/or may be interfered with by uplink signal 820 and/or downlink signal 822. However, if the measured interference does not exceed the threshold (or on the other hand does not meet the threshold), the second or third wireless device 814, 816 may determine that the D2D signal 826 is unlikely to introduce interference 828 into the uplink signal 820, and/or introduce interference 830 into the downlink signal 822, and/or may be interfered with by the uplink signal 820 and/or the downlink signal 822.

If the wireless device determines that the transmission condition indicates that the communication of the wireless device may interfere with the other communication, the wireless device may proceed to operation 910. At operation 910, the wireless device may select a first set of open loop power control parameters based on transmission conditions. The wireless device may use the first set of open-loop power control parameters to control the transmission power based on a power control algorithm. For example, the first set of open loop power control parameters may cause the wireless device to increase or decrease the transmission power of the wireless device.

In the context of fig. 8, the first wireless device may perform a selection operation 832 to select a first set of open-loop power control parameters (e.g., other than a default set). Also in the context of fig. 8, the second wireless device may perform a selection operation 834 to select the first set of open-loop power control parameters (e.g., other than the default set). Similarly, the third wireless device may perform a select operation 836 to select a first set of open-loop power control parameters (e.g., different from the default set).

If the wireless device determines that the transmission conditions indicate that the communication of the wireless device is unlikely to interfere with the other communication, the wireless device may proceed to operation 912. At operation 912, the wireless device may select a second set of open loop power control parameters based on the transmission conditions. The wireless device may use a second set of open loop power control parameters to control the transmission power based on the power control algorithm. For example, the first set of open loop power control parameters may cause the wireless device to set a transmission power of the wireless device to a default level.

In the context of fig. 8, the first wireless device may perform a selection operation 832 to select a second set (e.g., a default set) of open-loop power control parameters. Also in the context of fig. 8, the second wireless device may perform a selection operation 834 to select a second set (e.g., a default set) of open-loop power control parameters. Similarly, the third wireless device may perform a select operation 836 to select a second set (e.g., a default set) of open-loop power control parameters.

At operation 914, the wireless device may transmit over the wireless channel at a power based on the selected set of open-loop power control parameters. For example, the wireless device may calculate the transmit power using a power control algorithm that takes into account the selected set of open-loop power control parameters.

In the context of fig. 8, the first wireless device 806 may calculate a transmission power using a selected set of open-loop power control parameters and transmit an uplink signal 820 according to the selected set. Also in the context of fig. 8, the second wireless device 814 or the third wireless device 816 may calculate a transmit power using the selected set of open-loop power control parameters and transmit a D2D signal 826 according to the selected set.

Fig. 10 is a conceptual data flow diagram 1000 illustrating the data flow between different modules/means/components in an exemplary apparatus 1002. The method may be performed by a wireless device (e.g., such as one of the wireless devices 806, 814, 816 of fig. 8, the apparatus 1100/1002' of fig. 11, etc.). The equipment 1002 depicts example connections and/or data between different modules/devices/components. It is to be understood that such connections and/or data flows are to be considered illustrative, and thus different and/or additional connections and/or data flows may exist in different aspects.

The apparatus 1002 may include a receiving component 1004 and a transmitting component 1010. Receiving component 1004 can receive signals from base stations and/or wireless devices (e.g., base station 1050 and/or wireless device 1052). In an aspect, receiving component 1004 may receive one or more open loop power control parameters (e.g., from base station 1050). In another aspect, receiving component 1004 may receive an indication of resources to be used by another wireless device (e.g., wireless device 1052) for another communication. In another aspect, receiving component 1004 may receive an interfering signal from another wireless device (e.g., wireless device 1052).

The apparatus 1002 may include a determination component 1012. Determining component 1012 can receive signals from base stations and/or wireless devices through receiving component 1004. Based on the received signal, determining component 1012 may determine a transmission condition, e.g., indicating whether the resource assigned by the apparatus may interfere with a resource assigned by another wireless device (e.g., wireless device 1052) to another communication.

For example, the determining component 1012 can receive an indication of resources assigned to other communications by the other wireless device 1052 from the base station 1050 through the receiving component 1004. A determination component 1012 may determine whether the indicated resources overlap with resources over which the apparatus 1002 will communicate. In another aspect, the determining component 1012 may measure the energy (or power) of the signal received by the receiving component 1004 and compare the measured energy to a threshold to determine whether interference is likely.

The determination component can provide an indication of the transmission status to the selection component 1014. Determining component 1012 may indicate whether resources for another communication overlap with resources over which the apparatus will communicate and/or whether a measured interference energy exceeds a threshold. Based on the indication of the transmission condition, the selecting component 1014 may select a set of open loop power control parameters. The selection component 1014 can be provided with at least one set of open loop power control parameters from the receiving component 1004.

The selecting component 1014 may select the first set of open loop power control parameters if the transmission conditions indicate that it is likely that the communication of the apparatus 1002 may interfere with other communications, such as communications from the other wireless device 1052. The first set of open loop power control parameters may be different from a default set. Alternatively, selecting component 1014 may select a second set of open loop power control parameters if the transmission conditions indicate that the communication of apparatus 1002 is unlikely to interfere with other communications. The second set of open loop power control parameters may be a default set.

The apparatus may include additional components that perform each block of the algorithm in the aforementioned flow chart of fig. 9. As such, each block in the aforementioned flow diagram of fig. 9 may be performed by a component and the apparatus may include one or more of these components. These components may be one or more hardware components specifically configured to implement the processes/algorithms, implemented by a processor configured to execute the processes/algorithms, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

Fig. 11 is a diagram 1100 illustrating an example of a hardware implementation of an apparatus 1002' employing a processing system 1114. The processing system 1114 may be implemented with a bus architecture, represented generally by the bus 1124. The bus 1124 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1114 and the overall design constraints. The bus 1124 links together various circuits including one or more processors and/or hardware modules (represented by the processor 1104, the components 1004, 1010, 1012, 1014, and the computer-readable medium/memory 1106). The bus 1124 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system 1114 may be coupled to the transceiver 1110. The transceiver 1110 is coupled to one or more antennas 1120. The transceiver 1110 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 1110 receives a signal from the one or more antennas 1120, extracts information from the received signal, and provides the extracted information to the processing system 1114 (and in particular the receiving component 1004). Additionally, the transceiver 1110 receives information from the processing system 1114 (and in particular the transmission component 1010) and generates a signal to be applied to the one or more antennas 1120 based on the received information. The processing system 1114 includes a processor 1104 coupled to a computer-readable medium/memory 1106. The processor 1104 is responsible for general processing, including the execution of software stored on the computer-readable medium/memory 1106. The software, when executed by the processor 1104, causes the processing system 1114 to perform the various functions described supra for any particular apparatus. The computer-readable medium/memory 1106 may also be used for storing data that is manipulated by the processor 1104 when executing software. The processing system further includes at least one of the components 1004, 1010, 1012, 1014. These components may be software components running in the processor 1104, resident/stored in the computer readable medium/memory 1106, one or more hardware components coupled to the processor 1104, or some combination thereof. The processing system 1114 may be a component of the UE 650 and may include the memory 660 and/or at least one of the TX processor 668, the RX processor 656, and the controller/processor 659.

In a configuration, the apparatus 1100/1002' for wireless communication includes means for determining, by a first UE, a transmission condition associated with communication over a wireless channel. The apparatus may further include means for selecting, by the first UE, a set of open-loop power control parameters of the at least two sets of open-loop power control parameters based on the transmission condition. The apparatus may further include means for transmitting, by the first UE, on the wireless channel at a power based on the selected set of open-loop power control parameters.

In an aspect of the apparatus 1100/1002', each set of the plurality of sets of parameters includes a first parameter associated with a semi-static base power level and a second parameter associated with path loss compensation. In an aspect of the apparatus 1100/1002', the communication over the wireless channel includes uplink communication with the base station through WWAN communication. In an aspect of the apparatus 1100/1002', the transmission condition is associated with D2D communication by a second UE, and the means for determining the transmission condition over the wireless channel is configured to determine whether the first UE is causing interference to the second UE.

In an aspect of the apparatus 1100/1002', the means for determining whether the first UE is causing interference to the second UE is configured to determine whether the second UE is communicating over D2D communications on the same set of resources to be used by the first UE for WWAN communications. In an aspect of the apparatus 1100/1002', the means for selecting the set of open-loop power control parameters is configured to select a first set of open-loop power control parameters when the first UE determines that the second UE is communicating on a same set of resources to be used by the first UE for WWAN communication, and to select a second set of open-loop power control parameters when the first UE determines that the second UE is communicating on a different set of resources to be used by the first UE for WWAN communication, wherein the second set of open-loop power control parameters is different than the first set of open-loop power control parameters.

In an aspect of the apparatus 1100/1002', the transmission condition is associated with an allocation between D2D resources and WWAN resources of a neighboring base station. In an aspect of the apparatus 1100/1002', the means for selecting the set of open-loop power control parameters is configured to select a first set of open-loop power control parameters when the first UE determines that communication over the wireless channel is on at least one resource that overlaps with an allocated D2D resource of a neighboring base station, and to select a second set of open-loop power control parameters when the first UE determines that communication over the wireless channel is on at least one resource that overlaps with an allocated WWAN resource of the neighboring base station, wherein the second set of open-loop power control parameters is different from the first set of open-loop power control parameters.

In an aspect of the apparatus 1100/1002', the communication over the wireless channel includes D2D communication with a second UE. In an aspect of the apparatus 1100/1002', the transmission condition is associated with WWAN communication by a third UE, wherein the means for determining the transmission condition over the wireless channel is configured to determine whether the third UE is causing interference to the first UE.

In an aspect of the apparatus 1100/1002', the means for determining whether the third UE is causing interference is configured to determine whether the third UE is communicating over the WWAN on the same set of resources to be used by the first UE for D2D communication. In an aspect of the apparatus 1100/1002', the means for selecting the set of open-loop power control parameters is configured to select a first set of open-loop power control parameters when the first UE determines that a third UE is communicating on the same set of resources to be used by the first UE for D2D communications, and to select a second set of open-loop power control parameters when the first UE determines that the third UE is communicating on a different set of resources to be used by the first UE for D2D communications, wherein the second set of open-loop power control parameters is different from the first set of open-loop power control parameters.

In an aspect of the apparatus 1100/1002', the D2D communication is a D2D discovery, and the means for transmitting is configured to transmit a discovery signal for the D2D discovery based on the selected set of open-loop power control parameters. In an aspect of apparatus 1100/1002', the D2D communication is over a physical side link shared channel (psch) or a physical side link control channel (PSCCH), and the means for transmitting is configured to transmit at least one of: transmitting data over the PSSCH based on the selected set of open-loop power control parameters or transmitting control information over the PSCCH based on the selected set of open-loop power control parameters.

The aforementioned means may be the aforementioned components of apparatus 1100 and/or one or more components of processing system 1114 of apparatus 1002' configured to perform the functions recited by the aforementioned means. As described supra, the processing system 1114 may include the TX processor 668, the RX processor 656, and the controller/processor 659. As such, in one configuration, the aforementioned means may be the TX processor 668, the RX processor 656, and the controller/processor 659 configured to perform the functions recited by the aforementioned means.

It should be understood that the specific order or hierarchy of blocks in the processes/flow diagrams disclosed is an illustration of exemplary approaches. It will be appreciated that the specific order or hierarchy of blocks in the processes/flow diagrams may be rearranged based on design preferences. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects. The term "some" means one or more unless specifically stated otherwise. Combinations such as "A, B or at least one of C", "A, B and at least one of C", and "A, B, C or any combination thereof" include any combination of A, B and/or C, and may include a plurality of a, a plurality of B, or a plurality of C. In particular, combinations such as "at least one of A, B or C", "at least one of A, B and C", and "A, B, C or any combination thereof" may be a only, B only, C, A and B, A and C, B and C only, or a and B and C, wherein any such combination may contain one or more members of A, B or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element should be construed as a means-plus-function unless the element is explicitly recited as using the phrase "means for … …".

Claims (28)

1. A method of wireless communication of a first user equipment, UE, the method comprising:

determining, by the first UE, a transmission condition associated with communication over a wireless channel, wherein determining a transmission condition comprises measuring energy on one or more resources, and wherein the transmission condition is associated with the measured energy on the one or more resources;

selecting, by the first UE, based on the transmission condition, a set of open-loop power control parameters of at least two sets of open-loop power control parameters, each of the at least two sets of open-loop power control parameters including a respective first parameter associated with a semi-static base power level and a respective second parameter associated with a pathloss compensation, wherein the at least two sets of open-loop power control parameters include a first set of open-loop power control parameters for use when the transmission condition is below a threshold and a second set of open-loop power control parameters for use when the transmission condition is above a threshold; and

transmitting, by the first UE, on the wireless channel at a power based on the selected set of open-loop power control parameters.

2. The method of claim 1, wherein the communication over the wireless channel comprises uplink communication with a base station through wireless wide area network (WW AN) communication.

3. The method of claim 2, wherein the transmission condition is associated with a device-to-device (D2D) communication by a second UE, and wherein determining the transmission condition on the wireless channel comprises determining whether the first UE is causing interference to the second UE.

4. The method of claim 3, wherein determining whether the first UE is causing interference to the second UE comprises: determining whether the second UE is performing D2D communications on the same set of resources to be used by the first UE for the WW AN communications.

5. The method of claim 4, wherein selecting the set of open-loop power control parameters comprises:

selecting the second set of open-loop power control parameters when the first UE determines that the second UE is communicating on the same set of resources to be used by the first UE for the WW AN communication; and

selecting the first set of open-loop power control parameters when the first UE determines that the second UE is communicating on a different set of resources to be used by the first UE for the WW AN communication,

wherein the second set of open loop power control parameters is different from the first set of open loop power control parameters.

6. The method of claim 2, wherein the transmission condition is associated with an allocation between device-to-device D2D resources and WWAN resources of a neighboring base station.

7. The method of claim 6, wherein selecting the set of open-loop power control parameters comprises:

selecting the second set of open-loop power control parameters when the first UE determines that communication over the wireless channel is on at least one resource that overlaps with the allocated D2D resource of the neighboring base station; and

selecting the first set of open-loop power control parameters when the first UE determines that communication over the wireless channel is on at least one resource that overlaps with the allocated WW AN resource of the neighboring base station,

wherein the second set of open loop power control parameters is different from the first set of open loop power control parameters.

8. The method of claim 1, wherein the communication over the wireless channel comprises D2D communication with a second UE.

9. The method of claim 8, wherein the transmission condition is associated with WW AN communication conducted by a third UE, wherein determining the transmission condition over the wireless channel comprises determining whether the third UE is causing interference to the first UE.

10. The method of claim 9, wherein determining whether the third UE is causing interference comprises determining whether the third UE is communicating over the WWAN on a same set of resources to be used by the first UE for the D2D communication.

11. The method of claim 10, wherein selecting the set of open-loop power control parameters comprises:

selecting the second set of open-loop power control parameters when the first UE determines that the third UE is communicating on the same set of resources to be used by the first UE for the D2D communication; and

selecting the first set of open-loop power control parameters when the first UE determines that the third UE is communicating on a different set of resources than resources to be used by the first UE for the D2D communication,

wherein the second set of open loop power control parameters is different from the first set of open loop power control parameters.

12. The method of claim 8, wherein the D2D communication is a D2D discovery, and the transmitting comprises transmitting a discovery signal for D2D discovery based on the selected set of open-loop power control parameters.

13. The method of claim 8, wherein the D2D communication is performed over a physical side link shared channel psch or a physical side link control channel PSCCH, and the transmitting comprises at least one of: data is transmitted over the PSSCH based on the selected set of open-loop power control parameters, or control information is transmitted over the PSCCH based on the selected set of open-loop power control parameters.

14. An apparatus for wireless communication for a first User Equipment (UE), the apparatus comprising:

means for determining, by the first UE, a transmission condition associated with communication over a wireless channel, wherein the means for determining the transmission condition comprises means for measuring energy on one or more resources, and wherein the transmission condition is associated with the measured energy on the one or more resources;

means for selecting, by the first UE, a set of open-loop power control parameters of at least two sets of open-loop power control parameters based on the transmission condition, each of the at least two sets of open-loop power control parameters comprising a respective first parameter associated with a semi-static base power level and a respective second parameter associated with path loss compensation, wherein the at least two sets of open-loop power control parameters comprise a first set of open-loop power control parameters for use when the transmission condition is below a threshold and a second set of open-loop power control parameters for use when the transmission condition is above a threshold; and

means for transmitting, by the first UE, over a wireless channel at a power based on the selected set of open-loop power control parameters.

15. The apparatus of claim 14, wherein the communication over the wireless channel comprises uplink communication with a base station over wireless wide area network (WW AN) communication.

16. The apparatus of claim 15, wherein the transmission condition is associated with device-to-device D2D communication by a second UE, and wherein the means for determining the transmission condition over the wireless channel is configured to determine whether the first UE is causing interference to the second UE.

17. The apparatus of claim 16, wherein the means for determining whether the first UE causes interference to the second UE is configured to determine whether the second UE is performing D2D communications on a same set of resources to be used by the first UE for the WWAN communications.

18. The apparatus of claim 15, wherein the transmission condition is associated with an allocation between device-to-device D2D resources and WWAN resources of a neighboring base station.

19. The apparatus of claim 14, wherein the communication over the wireless channel comprises D2D communication with a second UE.

20. The apparatus of claim 19, wherein the transmission condition is associated with WWAN communication by a third UE, wherein the means for determining the transmission condition over the wireless channel is configured to determine whether the third UE is causing interference to the first UE.

21. The apparatus of claim 20, wherein the means for determining whether the third UE is causing interference is configured to determine whether the third UE is communicating over the WWAN on a same set of resources to be used by the first UE for the D2D communication.

22. The apparatus of claim 20, wherein the D2D communication is a D2D discovery, and the means for transmitting is configured to transmit a discovery signal for D2D discovery based on the selected set of open-loop power control parameters.

23. An apparatus for wireless communication for a first User Equipment (UE), the apparatus comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor configured to:

determining, by the first UE, a transmission condition associated with communication over a wireless channel, wherein the at least one processor is configured to measure energy on one or more resources, and wherein the transmission condition is associated with the measured energy on the one or more resources;

selecting, by the first UE, based on the transmission condition, a set of open-loop power control parameters of at least two sets of open-loop power control parameters, each of the at least two sets of open-loop power control parameters including a respective first parameter associated with a semi-static base power level and a respective second parameter associated with a pathloss compensation, wherein the at least two sets of open-loop power control parameters include a first set of open-loop power control parameters for use when the transmission condition is below a threshold and a second set of open-loop power control parameters for use when the transmission condition is above a threshold; and

transmitting, by the first UE, over a wireless channel at a power based on the selected set of open-loop power control parameters.

24. The apparatus of claim 23, wherein the communication over the wireless channel comprises uplink communication with a base station over wireless wide area network (WW AN) communication.

25. The apparatus of claim 24, wherein the transmission condition is associated with device-to-device D2D communication by a second UE, and the at least one processor is configured to determine the transmission condition over the wireless channel based on determining whether the first UE is causing interference to the second UE.

26. The apparatus of claim 24, wherein the transmission condition is associated with an allocation between device-to-device D2D resources and WWAN resources of a neighboring base station.

27. The apparatus of claim 23, wherein the communication over the wireless channel comprises D2D communication with a second UE.

28. A computer-readable medium storing computer executable code for wireless communication by a first user equipment, UE, the computer executable code for causing a processor to:

determining, by the first UE, a transmission condition associated with communication over a wireless channel, wherein the computer-executable code further causes the processor to measure energy on one or more resources, and wherein the transmission condition is associated with the measured energy on the one or more resources;

selecting, by the first UE, based on the transmission condition, a set of open-loop power control parameters of at least two sets of open-loop power control parameters, each of the at least two sets of open-loop power control parameters including a respective first parameter associated with a semi-static base power level and a respective second parameter associated with a pathloss compensation, wherein the at least two sets of open-loop power control parameters include a first set of open-loop power control parameters for use when the transmission condition is below a threshold and a second set of open-loop power control parameters for use when the transmission condition is above a threshold; and

transmitting, by the first UE, on the wireless channel at a power based on the selected set of open-loop power control parameters.

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